/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.
Copyright (C) 2006 Robert Beckebans <trebor_7@users.sourceforge.net>

This file is part of XreaL source code.

XreaL source code is free software; you can redistribute it
and/or modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the License,
or (at your option) any later version.

XreaL source code is distributed in the hope that it will be
useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with XreaL source code; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/
// cmdlib.c

#include "cmdlib.h"
#include "mathlib.h"
#include "inout.h"
#include <sys/types.h>
#include <sys/stat.h>

#ifdef WIN32
#include <direct.h>
#include <windows.h>
#endif

#if defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__)
#include <unistd.h>
#endif

#ifdef NeXT
#include <libc.h>
#endif

#define	BASEDIRNAME	"dretchstorm"		// assumed to have a 2 or 3 following
#define PATHSEPERATOR   '/'

#ifdef SAFE_MALLOC
void           *safe_malloc(size_t size)
{
	void           *p;

	p = malloc(size);
	if(!p)
		Error("safe_malloc failed on allocation of %i bytes", size);

	return p;
}

void           *safe_malloc_info(size_t size, char *info)
{
	void           *p;

	p = malloc(size);
	if(!p)
		Error("%s: safe_malloc failed on allocation of %i bytes", info, size);

	return p;
}
#endif

// set these before calling CheckParm
int             myargc;
char          **myargv;

char            com_token[1024];
qboolean        com_eof;

qboolean        archive;
char            archivedir[1024];



/*
===================
ExpandWildcards

Mimic unix command line expansion
===================
*/
#define	MAX_EX_ARGC	1024
int             ex_argc;
char           *ex_argv[MAX_EX_ARGC];

#ifdef _WIN32
#include "io.h"
void ExpandWildcards(int *argc, char ***argv)
{
	struct _finddata_t fileinfo;
	int             handle;
	int             i;
	char            filename[1024];
	char            filebase[1024];
	char           *path;

	ex_argc = 0;
	for(i = 0; i < *argc; i++)
	{
		path = (*argv)[i];
		if(path[0] == '-' || (!strstr(path, "*") && !strstr(path, "?")))
		{
			ex_argv[ex_argc++] = path;
			continue;
		}

		handle = _findfirst(path, &fileinfo);
		if(handle == -1)
			return;

		ExtractFilePath(path, filebase);

		do
		{
			sprintf(filename, "%s%s", filebase, fileinfo.name);
			ex_argv[ex_argc++] = copystring(filename);
		} while(_findnext(handle, &fileinfo) != -1);

		_findclose(handle);
	}

	*argc = ex_argc;
	*argv = ex_argv;
}
#else
void ExpandWildcards(int *argc, char ***argv)
{
}
#endif

/*

qdir will hold the path up to the quake directory, including the slash

  f:\quake\
  /raid/quake/

gamedir will hold qdir + the game directory (id1, id2, etc)

*/

char            qdir[1024];
char            gamedir[1024];
char            writedir[1024];

void SetQdirFromPath(const char *path)
{
	char            temp[1024];
	const char     *c;
	const char     *sep;
	int             len, count;

	if(!(path[0] == '/' || path[0] == '\\' || path[1] == ':'))
	{							// path is partial
		Q_getwd(temp);
		strcat(temp, path);
		path = temp;
	}

	// search for "quake2" in path

	len = strlen(BASEDIRNAME);
	for(c = path + strlen(path) - 1; c != path; c--)
	{
		int             i;

		if(!Q_strncasecmp(c, BASEDIRNAME, len))
		{
			//
			//strncpy (qdir, path, c+len+2-path);
			// the +2 assumes a 2 or 3 following quake which is not the
			// case with a retail install
			// so we need to add up how much to the next separator
			sep = c + len;
			count = 1;
			while(*sep && *sep != '/' && *sep != '\\')
			{
				sep++;
				count++;
			}
			strncpy(qdir, path, c + len + count - path);
			Sys_Printf("qdir: %s\n", qdir);
			for(i = 0; i < strlen(qdir); i++)
			{
				if(qdir[i] == '\\')
					qdir[i] = '/';
			}

			c += len + count;
			while(*c)
			{
				if(*c == '/' || *c == '\\')
				{
					strncpy(gamedir, path, c + 1 - path);

					for(i = 0; i < strlen(gamedir); i++)
					{
						if(gamedir[i] == '\\')
							gamedir[i] = '/';
					}

					Sys_Printf("gamedir: %s\n", gamedir);

					if(!writedir[0])
						strcpy(writedir, gamedir);
					else if(writedir[strlen(writedir) - 1] != '/')
					{
						writedir[strlen(writedir)] = '/';
						writedir[strlen(writedir) + 1] = 0;
					}

					return;
				}
				c++;
			}
			Error("No gamedir in %s", path);
			return;
		}
	}
	Error("SetQdirFromPath: no '%s' in %s", BASEDIRNAME, path);
}

char           *ExpandArg(const char *path)
{
	static char     full[1024];

	if(path[0] != '/' && path[0] != '\\' && path[1] != ':')
	{
		Q_getwd(full);
		strcat(full, path);
	}
	else
		strcpy(full, path);
	return full;
}

char           *ExpandPath(const char *path)
{
	static char     full[1024];

	if(!qdir)
		Error("ExpandPath called without qdir set");
	if(path[0] == '/' || path[0] == '\\' || path[1] == ':')
	{
		strcpy(full, path);
		return full;
	}
	sprintf(full, "%s%s", qdir, path);
	return full;
}

char           *ExpandGamePath(const char *path)
{
	static char     full[1024];

	if(!qdir)
		Error("ExpandGamePath called without qdir set");
	if(path[0] == '/' || path[0] == '\\' || path[1] == ':')
	{
		strcpy(full, path);
		return full;
	}
	sprintf(full, "%s%s", gamedir, path);
	return full;
}

char           *ExpandPathAndArchive(const char *path)
{
	char           *expanded;
	char            archivename[1024];

	expanded = ExpandPath(path);

	if(archive)
	{
		sprintf(archivename, "%s/%s", archivedir, path);
		QCopyFile(expanded, archivename);
	}
	return expanded;
}


char           *copystring(const char *s)
{
	char           *b;

	b = safe_malloc(strlen(s) + 1);
	strcpy(b, s);
	return b;
}



/*
================
I_FloatTime
================
*/
double I_FloatTime(void)
{
	time_t          t;

	time(&t);

	return t;
#if 0
// more precise, less portable
	struct timeval  tp;
	struct timezone tzp;
	static int      secbase;

	gettimeofday(&tp, &tzp);

	if(!secbase)
	{
		secbase = tp.tv_sec;
		return tp.tv_usec / 1000000.0;
	}

	return (tp.tv_sec - secbase) + tp.tv_usec / 1000000.0;
#endif
}

void Q_getwd(char *out)
{
	int             i = 0;

#ifdef WIN32
	_getcwd(out, 256);
	strcat(out, "\\");
#else
	// Gef: Changed from getwd() to getcwd() to avoid potential buffer overflow
	getcwd(out, 256);
	strcat(out, "/");
#endif

	while(out[i] != 0)
	{
		if(out[i] == '\\')
			out[i] = '/';
		i++;
	}
}


void Q_mkdir(const char *path)
{
#ifdef WIN32
	if(_mkdir(path) != -1)
		return;
#else
	if(mkdir(path, 0777) != -1)
		return;
#endif
	if(errno != EEXIST)
		Error("mkdir %s: %s", path, strerror(errno));
}

/*
============
FileTime

returns -1 if not present
============
*/
int FileTime(const char *path)
{
	struct stat     buf;

	if(stat(path, &buf) == -1)
		return -1;

	return buf.st_mtime;
}



/*
==============
Com_Parse

Parse a token out of a string
==============
*/
char           *Com_Parse(char *data)
{
	int             c;
	int             len;

	len = 0;
	com_token[0] = 0;

	if(!data)
		return NULL;

// skip whitespace
  skipwhite:
	while((c = *data) <= ' ')
	{
		if(c == 0)
		{
			com_eof = qtrue;
			return NULL;		// end of file;
		}
		data++;
	}

// skip // comments
	if(c == '/' && data[1] == '/')
	{
		while(*data && *data != '\n')
			data++;
		goto skipwhite;
	}


// handle quoted strings specially
	if(c == '\"')
	{
		data++;
		do
		{
			c = *data++;
			if(c == '\"')
			{
				com_token[len] = 0;
				return data;
			}
			com_token[len] = c;
			len++;
		} while(1);
	}

// parse single characters
	if(c == '{' || c == '}' || c == ')' || c == '(' || c == '\'' || c == ':')
	{
		com_token[len] = c;
		len++;
		com_token[len] = 0;
		return data + 1;
	}

// parse a regular word
	do
	{
		com_token[len] = c;
		data++;
		len++;
		c = *data;
		if(c == '{' || c == '}' || c == ')' || c == '(' || c == '\'' || c == ':')
			break;
	} while(c > 32);

	com_token[len] = 0;
	return data;
}

int Q_strncasecmp(const char *s1, const char *s2, int n)
{
	int             c1, c2;

	do
	{
		c1 = *s1++;
		c2 = *s2++;

		if(!n--)
			return 0;			// strings are equal until end point

		if(c1 != c2)
		{
			if(c1 >= 'a' && c1 <= 'z')
				c1 -= ('a' - 'A');
			if(c2 >= 'a' && c2 <= 'z')
				c2 -= ('a' - 'A');
			if(c1 != c2)
				return -1;		// strings not equal
		}
	} while(c1);

	return 0;					// strings are equal
}

int Q_stricmp(const char *s1, const char *s2)
{
	return Q_strncasecmp(s1, s2, 99999);
}

/*
=============
Q_strncpyz
 
Safe strncpy that ensures a trailing zero
=============
*/
void Q_strncpyz(char *dest, const char *src, int destsize)
{
	if(!dest)
	{
		Error("Q_strncpyz: NULL dest");
	}
	if(!src)
	{
		Error("Q_strncpyz: NULL src");
	}
	if(destsize < 1)
	{
		Error("Q_strncpyz: destsize < 1");
	}

	strncpy(dest, src, destsize - 1);
	dest[destsize - 1] = 0;
}

// never goes past bounds or leaves without a terminating 0
void Q_strcat(char *dest, int destsize, const char *src)
{
	int             l1;

	l1 = strlen(dest);
	if(l1 >= destsize)
	{
		Error("Q_strcat: already overflowed");
	}
	Q_strncpyz(dest + l1, src, destsize - l1);
}

// NOTE TTimo when switching to Multithread DLL (Release/Debug) in the config
//   started getting warnings about that function, prolly a duplicate with the runtime function
//   maybe we still need to have it in linux builds
/*
char *strupr (char *start)
{
	char	*in;
	in = start;
	while (*in)
	{
		*in = toupper(*in);
		in++;
	}
	return start;
}
*/

char           *strlower(char *start)
{
	char           *in;

	in = start;
	while(*in)
	{
		*in = tolower(*in);
		in++;
	}
	return start;
}

/*
============
va

does a varargs printf into a temp buffer, so I don't need to have
varargs versions of all text functions.
FIXME: make this buffer size safe someday
============
*/
char           *va(char *format, ...)
{
	va_list         argptr;
	static char     string[2][32000];	// in case va is called by nested functions
	static int      index = 0;
	char           *buf;

	buf = string[index & 1];
	index++;

	va_start(argptr, format);
	vsprintf(buf, format, argptr);
	va_end(argptr);

	return buf;
}


/*
=============================================================================

						MISC FUNCTIONS

=============================================================================
*/


/*
=================
CheckParm

Checks for the given parameter in the program's command line arguments
Returns the argument number (1 to argc-1) or 0 if not present
=================
*/
int CheckParm(const char *check)
{
	int             i;

	for(i = 1; i < myargc; i++)
	{
		if(!Q_stricmp(check, myargv[i]))
			return i;
	}

	return 0;
}



/*
================
Q_filelength
================
*/
int Q_filelength(FILE * f)
{
	int             pos;
	int             end;

	pos = ftell(f);
	fseek(f, 0, SEEK_END);
	end = ftell(f);
	fseek(f, pos, SEEK_SET);

	return end;
}


FILE           *SafeOpenWrite(const char *filename)
{
	FILE           *f;

	f = fopen(filename, "wb");

	if(!f)
		Error("Error opening %s: %s", filename, strerror(errno));

	return f;
}

FILE           *SafeOpenRead(const char *filename)
{
	FILE           *f;

	f = fopen(filename, "rb");

	if(!f)
		Error("Error opening %s: %s", filename, strerror(errno));

	return f;
}


void SafeRead(FILE * f, void *buffer, int count)
{
	if(fread(buffer, 1, count, f) != (size_t) count)
		Error("File read failure");
}


void SafeWrite(FILE * f, const void *buffer, int count)
{
	if(fwrite(buffer, 1, count, f) != (size_t) count)
		Error("File write failure");
}


/*
==============
FileExists
==============
*/
qboolean FileExists(const char *filename)
{
	FILE           *f;

	f = fopen(filename, "r");
	if(!f)
		return qfalse;
	fclose(f);
	return qtrue;
}

/*
==============
LoadFile
==============
*/
int LoadFile(const char *filename, void **bufferptr)
{
	FILE           *f;
	int             length;
	void           *buffer;

	f = SafeOpenRead(filename);
	length = Q_filelength(f);
	buffer = safe_malloc(length + 1);
	((char *)buffer)[length] = 0;
	SafeRead(f, buffer, length);
	fclose(f);

	*bufferptr = buffer;
	return length;
}


/*
==============
LoadFileBlock
-
rounds up memory allocation to 4K boundry
-
==============
*/
int LoadFileBlock(const char *filename, void **bufferptr)
{
	FILE           *f;
	int             length, nBlock, nAllocSize;
	void           *buffer;

	f = SafeOpenRead(filename);
	length = Q_filelength(f);
	nAllocSize = length;
	nBlock = nAllocSize % MEM_BLOCKSIZE;
	if(nBlock > 0)
	{
		nAllocSize += MEM_BLOCKSIZE - nBlock;
	}
	buffer = safe_malloc(nAllocSize + 1);
	memset(buffer, 0, nAllocSize + 1);
	SafeRead(f, buffer, length);
	fclose(f);

	*bufferptr = buffer;
	return length;
}


/*
==============
TryLoadFile

Allows failure
==============
*/
int TryLoadFile(const char *filename, void **bufferptr)
{
	FILE           *f;
	int             length;
	void           *buffer;

	*bufferptr = NULL;

	f = fopen(filename, "rb");
	if(!f)
		return -1;
	length = Q_filelength(f);
	buffer = safe_malloc(length + 1);
	((char *)buffer)[length] = 0;
	SafeRead(f, buffer, length);
	fclose(f);

	*bufferptr = buffer;
	return length;
}


/*
==============
SaveFile
==============
*/
void SaveFile(const char *filename, const void *buffer, int count)
{
	FILE           *f;

	f = SafeOpenWrite(filename);
	SafeWrite(f, buffer, count);
	fclose(f);
}



void DefaultExtension(char *path, const char *extension)
{
	char           *src;

//
// if path doesnt have a .EXT, append extension
// (extension should include the .)
//
	src = path + strlen(path) - 1;

	while(*src != '/' && *src != '\\' && src != path)
	{
		if(*src == '.')
			return;				// it has an extension
		src--;
	}

	strcat(path, extension);
}


void DefaultPath(char *path, const char *basepath)
{
	char            temp[128];

	if(path[0] == '/' || path[0] == '\\')
		return;					// absolute path location
	strcpy(temp, path);
	strcpy(path, basepath);
	strcat(path, temp);
}


void StripFilename(char *path)
{
	int             length;

	length = strlen(path) - 1;
	while(length > 0 && path[length] != '/' && path[length] != '\\')
		length--;
	path[length] = 0;
}

void StripExtension(char *path)
{
	int             length;

	length = strlen(path) - 1;
	while(length > 0 && path[length] != '.')
	{
		length--;
		if(path[length] == '/' || path[length] == '\\')
			return;				// no extension
	}
	if(length)
		path[length] = 0;
}


/*
====================
Extract file parts
====================
*/
// FIXME: should include the slash, otherwise
// backing to an empty path will be wrong when appending a slash
void ExtractFilePath(const char *path, char *dest)
{
	const char     *src;

	src = path + strlen(path) - 1;

//
// back up until a \ or the start
//
	while(src != path && *(src - 1) != '\\' && *(src - 1) != '/')
		src--;

	memcpy(dest, path, src - path);
	dest[src - path] = 0;
}

void ExtractFileBase(const char *path, char *dest)
{
	const char     *src;

	src = path + strlen(path) - 1;

//
// back up until a \ or the start
//
	while(src != path && *(src - 1) != '/' && *(src - 1) != '\\')
		src--;

	while(*src && *src != '.')
	{
		*dest++ = *src++;
	}
	*dest = 0;
}

void ExtractFileExtension(const char *path, char *dest)
{
	const char     *src;

	src = path + strlen(path) - 1;

//
// back up until a . or the start
//
	while(src != path && *(src - 1) != '.')
		src--;
	if(src == path)
	{
		*dest = 0;				// no extension
		return;
	}

	strcpy(dest, src);
}


/*
==============
ParseNum / ParseHex
==============
*/
int ParseHex(const char *hex)
{
	const char     *str;
	int             num;

	num = 0;
	str = hex;

	while(*str)
	{
		num <<= 4;
		if(*str >= '0' && *str <= '9')
			num += *str - '0';
		else if(*str >= 'a' && *str <= 'f')
			num += 10 + *str - 'a';
		else if(*str >= 'A' && *str <= 'F')
			num += 10 + *str - 'A';
		else
			Error("Bad hex number: %s", hex);
		str++;
	}

	return num;
}


int ParseNum(const char *str)
{
	if(str[0] == '$')
		return ParseHex(str + 1);
	if(str[0] == '0' && str[1] == 'x')
		return ParseHex(str + 2);
	return atol(str);
}



/*
============================================================================

					BYTE ORDER FUNCTIONS

============================================================================
*/

#ifdef _SGI_SOURCE
#define	__BIG_ENDIAN__
#endif

#ifdef __BIG_ENDIAN__

short LittleShort(short l)
{
	byte            b1, b2;

	b1 = l & 255;
	b2 = (l >> 8) & 255;

	return (b1 << 8) + b2;
}

short BigShort(short l)
{
	return l;
}


int LittleLong(int l)
{
	byte            b1, b2, b3, b4;

	b1 = l & 255;
	b2 = (l >> 8) & 255;
	b3 = (l >> 16) & 255;
	b4 = (l >> 24) & 255;

	return ((int)b1 << 24) + ((int)b2 << 16) + ((int)b3 << 8) + b4;
}

int BigLong(int l)
{
	return l;
}


float LittleFloat(float l)
{
	union
	{
		byte            b[4];
		float           f;
	} in           , out;

	in.f = l;
	out.b[0] = in.b[3];
	out.b[1] = in.b[2];
	out.b[2] = in.b[1];
	out.b[3] = in.b[0];

	return out.f;
}

float BigFloat(float l)
{
	return l;
}


#else


short BigShort(short l)
{
	byte            b1, b2;

	b1 = l & 255;
	b2 = (l >> 8) & 255;

	return (b1 << 8) + b2;
}

short LittleShort(short l)
{
	return l;
}


int BigLong(int l)
{
	byte            b1, b2, b3, b4;

	b1 = l & 255;
	b2 = (l >> 8) & 255;
	b3 = (l >> 16) & 255;
	b4 = (l >> 24) & 255;

	return ((int)b1 << 24) + ((int)b2 << 16) + ((int)b3 << 8) + b4;
}

int LittleLong(int l)
{
	return l;
}

float BigFloat(float l)
{
	union
	{
		byte            b[4];
		float           f;
	} in           , out;

	in.f = l;
	out.b[0] = in.b[3];
	out.b[1] = in.b[2];
	out.b[2] = in.b[1];
	out.b[3] = in.b[0];

	return out.f;
}

float LittleFloat(float l)
{
	return l;
}


#endif


//=======================================================


// FIXME: byte swap?

// this is a 16 bit, non-reflected CRC using the polynomial 0x1021
// and the initial and final xor values shown below...  in other words, the
// CCITT standard CRC used by XMODEM

#define CRC_INIT_VALUE	0xffff
#define CRC_XOR_VALUE	0x0000

static unsigned short crctable[256] = {
	0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
	0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
	0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
	0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
	0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
	0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
	0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
	0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
	0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
	0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
	0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
	0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
	0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
	0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
	0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
	0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
	0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
	0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
	0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
	0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
	0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
	0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
	0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
	0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
	0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
	0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
	0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
	0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
	0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
	0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
	0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
	0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0
};

void CRC_Init(unsigned short *crcvalue)
{
	*crcvalue = CRC_INIT_VALUE;
}

void CRC_ProcessByte(unsigned short *crcvalue, byte data)
{
	*crcvalue = (*crcvalue << 8) ^ crctable[(*crcvalue >> 8) ^ data];
}

unsigned short CRC_Value(unsigned short crcvalue)
{
	return crcvalue ^ CRC_XOR_VALUE;
}

//=============================================================================

/*
============
CreatePath
============
*/
void CreatePath(const char *path)
{
	const char     *ofs;
	char            c;
	char            dir[1024];

#ifdef _WIN32
	int             olddrive = -1;

	if(path[1] == ':')
	{
		olddrive = _getdrive();
		_chdrive(toupper(path[0]) - 'A' + 1);
	}
#endif

	if(path[1] == ':')
		path += 2;

	for(ofs = path + 1; *ofs; ofs++)
	{
		c = *ofs;
		if(c == '/' || c == '\\')
		{						// create the directory
			memcpy(dir, path, ofs - path);
			dir[ofs - path] = 0;
			Q_mkdir(dir);
		}
	}

#ifdef _WIN32
	if(olddrive != -1)
	{
		_chdrive(olddrive);
	}
#endif
}


/*
============
QCopyFile

  Used to archive source files
============
*/
void QCopyFile(const char *from, const char *to)
{
	void           *buffer;
	int             length;

	length = LoadFile(from, &buffer);
	CreatePath(to);
	SaveFile(to, buffer, length);
	free(buffer);
}

void Sys_Sleep(int n)
{
#ifdef WIN32
	Sleep(n);
#endif
#if defined (__linux__) || defined (__APPLE__)
	usleep(n * 1000);
#endif
}
